wlantest: Fix bip_protect() memory allocation

The addition operator is of higher precedence than the ternary
conditional and the construction here needs to use parentheses to
calculate the buffer length properly when generating test frames with
BIP protection.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

wlantest/bip.c

@@ -23,7 +23,7 @@ u8 * bip_protect(const u8 *igtk, size_t igtk_len, u8 *frame, size_t len,
 	struct ieee80211_hdr *hdr;
 	size_t plen;
 
-	plen = len + igtk_len == 32 ? 26 : 18;
+	plen = len + (igtk_len == 32 ? 26 : 18);
 	prot = os_malloc(plen);
 	if (prot == NULL)
 		return NULL;